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تسجيل مستخدم جديدThe radius and mass of the close solar twin 18 Sco derived from asteroseismology and interferometry
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The growing interest in solar twins is motivated by the possibility of comparing them directly to the Sun. To carry on this kind of analysis, we need to know their physical characteristics with precision. Our first objective is to use asteroseismology and interferometry on the brightest of them: 18 Sco. We observed the star during 12 nights with HARPS for seismology and used the PAVO beam-combiner at CHARA for interferometry. An average large frequency separation $134.4pm0.3$ $mu$Hz and angular and linear radiuses of $0.6759 pm 0.0062$ mas and $1.010pm0.009$ R$_{odot}$ were estimated. We used these values to derive the mass of the star, $1.02pm0.03$ M$_{odot}$.
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Solar twins are objects of great interest in that they allow us to understand better how stellar evolution and structure are affected by variations of the stellar mass, age and chemical composition in the vicinity of the commonly accepted solar value
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Solar twins have been a focus of attention for more than a decade, because their structure is extremely close to that of the Sun. Today, thanks to high-precision spectrometers, it is possible to use asteroseismology to probe their interiors. Our goal
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